Apparatus for delivering a tubular to a wellbore

ABSTRACT

An apparatus for delivering a tubular ( 9 ) to a well centre, which apparatus comprises means ( 13, 14 ) which, in use, inhibit swinging motion of the tubular ( 9 ) whilst it is suspended from an elevator.

This invention relates to an apparatus for delivering a tubular to awell centre.

During the construction of oil and gas wells a plurality of tubulars aretransferred from a storage area to the well centre. Typically, eachtubular is transferred to the V-slot adjacent the rig flow by aconveyor. The tubular is then lifted by an elevator and swung intoposition over the well centre ready for attachment to a string oftubulars extending down the well.

One of the difficulties associated with this process is that as theelevator moves the tubular, the tubular swings back and forth like agiant pendulum. This is potentially very hazardous, particularly whenhandling tubulars of large diameters.

An aim of at least preferred embodiments of the present invention is toreduce this problem.

According to one aspect of the present invention there is provided anapparatus for delivering a tubular to a well centre, which apparatuscomprises means which, in use, inhibit swinging motion of the tubularwhilst it is suspended from an elevator.

Preferably, said means comprises an arm which is pivotable between afirst position and a second position.

Advantageously, said arm is provided with a stub axle which is providedwith rollers for supporting said tubular.

Preferably, the apparatus further comprises a ramp which can be placedagainst a rig floor, and a tray which can support a tubular and be movedalong said ramp.

The ramp may define an angle with the horizontal of between 30 degreesand 70 degrees, but it is normally intended to be used at angles of from110 to 60 degrees.

In one embodiment, said arm is mounted on said ramp.

In another embodiment, said arm is mounted on said tray.

Alternatively, the arm may be mounted on the derrick.

Advantageously, said arm is rotatable about its axis to release saidtubular therefrom, for example by an hydraulic motor.

Preferably, the apparatus includes an hydraulic motor to pivot saidmeans.

According to another aspect of the present invention, there is providedan apparatus for delivering a tubular to a well centre, which apparatuscomprises a ramp which can be placed against a rig floor, a tray forcarrying said tubular and means which, in use, enables said tray toascend or descend said ramp.

Preferably, said ramp further comprises a rack.

Advantageously, said means is a pinion mounted on said tray andengageable with said rack.

The means by which the tray moves along the ramp may be of any suitablemeans, but is preferably a rack and pinion.

Preferably, said means comprises two pinions, one mounted adjacent eachend of said tray.

Advantageously, said tray further comprises a support wheel.

Preferably, said tray further comprises a pipe sledge mounted forlongitudinal movement therein.

Advantageously, said tray further comprises a pipe pusher mounted suchthat, in use, said pipe pusher moves said tubular longitudinally withinsaid tray.

According to another aspect of the present invention, there is providedan apparatus for delivering a tubular to a well centre, which apparatuscomprises a tray for supporting said tubular, and means which, in use,can apply a force to said tubular to move it longitudinally with respectto said tray.

Preferably, said means comprises a piston and cylinder.

Advantageously, said apparatus further comprises a ramp which can beplaced against a rig floor, and a tray which can be moved along saidramp.

For a better understanding of the present invention reference will nowbe made, by way of example, to the accompanying drawings, in which:

FIG. 1 is a side view of an apparatus in accordance with the presentinvention about to deliver a tubular to the well centre of a drillingplatform;

FIG. 2 is a side view, to an enlarged scale, of part of the apparatusshown in FIG. 1 with the tubular mounted thereon; and

FIGS. 3 to 9 show successive stages in the operation of the apparatus.

Referring to FIG. 1 there is shown an apparatus which is generallyidentified by reference numeral 1.

The apparatus 1 comprises a ramp 3 which extends upwardly to a rig floor2 and a pipe tray 4. The ramp 3 extends between the pipe tray 4 and aV-slot (not shown) in a derrick 5. The derrick 5 is provided with anelevator 6 which is supported from a top drive slidably mounted on atrack 7.

A tubular 8 is shown within the derrick 5 having been screwed orotherwise attached to a string of tubulars (not shown) which extend downa wellbore (not shown) at the well centre. A tubular 9 is shown restingon the pipe tray 4 and is to be attached to the tubular 8 in the processof increasing the length of the string of tubulars within the wellbore.

Referring now to FIG. 2 the ramp 3 further comprises a rack 10 whichextends from the lower end of ramp 3 to the upper end of ramp 3.

The pipe tray 4 further comprises two pinions 11, 12 which can berotated by respective hydraulic motors (not shown) so that, in use, thepipe tray 4 can move either up or down the rack 10. The pinion 11 islocated at one end of the pipe tray 4 whilst the pinion 12 is located atthe opposite end of pipe tray 4.

A stabbing arm 13 is pivotally mounted at the end of pipe tray 4 and maybe rotated by means of a swivel drive 14. Swivel drive 14 can beactuated by a hydraulic motor (not shown) to move the stabbing arm 13between a first position shown in FIG. 2 and a second position shown inFIG. 9 as more fully described hereafter. The stabbing arm 13 isprovided with a stub axle which carries rollers 19 to facilitatelongitudinal movement of the tubular 9.

A pipe sledge 15 resides within and at the rear end of the pipe tray 4.The pipe sledge 15 has rollers 20 mounted at each end so that in use thepipe sledge 15 can move along the longitudinal axis of the pipe tray 4.

A pipe pusher 16 which comprises a piston and cylinder is locatedsubstantially in abutment with the pipe sledge 15. The pipe pusher 16can be hydraulically activated so that the piston of the pipe pusher 16will exert a force on the pipe sledge 15 to move the tubular 9longitudinally within the pipe tray 4.

Elastomeric sliding plates 18 are provided along the length of pipe tray4 and allow the tubular 9 to rest therein. In use, the elastomericsliding plates 18 are movable within the pipe tray 4 to help support thetubular 9.

A support wheel 17 is located at the rear end of the pipe tray 4 which,in use, allows movement of the pipe tray 4 towards the V-slot in thederrick 5.

FIGS. 3 to 9 show the apparatus in use.

Prior to using the apparatus 1 the tubular 9 is rolled onto the pipetray 4 from a pipe deck (not shown). The pinion 11 is rotated. The teethof the pinion 11 engage the rack 10 moving the pipe tray 4 toward theV-slot (not shown) in the derrick 5, as shown in FIG. 3. The pinion 12is rotated as it nears the ramp 3 so that upon engagement with the ramp3 the pipe tray 4 continues to move toward the V-slot in the derrick 5.

As shown in FIGS. 4 and 5 the pinion 11 has left the ramp 3 but the pipetray 4 continues to move toward the V-slot in the derrick 5 under theeffect of the pinion 12. The pinions 11, 12 are stopped when the pipetray 4 has reached the position shown in FIG. 5.

The tubular 9 is pushed out of the pipe tray 4 by extending the pistonin the pipe pusher 16. The tubular 9 is pushed to a position where theelevator 6 can be easily attached to the tubular 9 as shown in FIG. 6.

FIG. 7 shows the elevator 6 having lifted the tubular 9 to a positionwhere the lower end of tubular 9 is near the rollers 19 of the stabbinglever 13 and the upper end is substantially above the well centre.

Swivel drive 14 is now engaged to rotate the stabbing lever 13 clockwisebetween the first position, shown in FIG. 7, and the second position,shown in FIG. 9. Movement of the stabbing lever 13 brings thelongitudinal axis of the tubular 9 from an inclined position withrespect to the longitudinal axis of the borehole (not shown), to aposition which is substantially in alignment with the axis of theborehole (FIG. 9) (weel centre). The rollers 19 allow substantiallyvertical movement of the tubular 9. Once this is completed the stabbinglever 13 is turned through 90° so that the stabbing lever 13 may bereturned to its first position. The pipe tray 4 can then return to itsinitial position by reversal of the pinion drives 11, 12 to collectanother tubular so that the process may be repeated.

What is claimed is:
 1. An apparatus for delivering a tubular to a wellcenter, which apparatus comprises a ramp which can be placed against arig floor, a tray for carrying said tubular, elastomeric sliding platesto support said tubular, and means which, in use, enables said tray toascend or descend said ramp.
 2. An apparatus as claimed in claim 1,wherein said ramp further comprises a rack.
 3. An apparatus as claimedin claim 1, wherein said means is a pinion mounted on said tray andengageable with a rack.
 4. An apparatus as claimed in claim 1, whereinsaid means comprises two pinions, one mounted adjacent each end of saidtray.
 5. An apparatus as claimed in claim 1, wherein said tray furthercomprises a support wheel.
 6. An apparatus as claimed in claim 5,wherein the tray further comprises a pipe sledge mounted forlongitudinal movement therein.
 7. An apparatus as claimed in claim 6,wherein said tray further comprises a pipe pusher mounted such that, inuse, the pipe pusher moves said tubular longitudinally within said tray.8. An apparatus for delivering a tubular to a well center, whichapparatus comprises a tray for supporting said tubular, a pinionoperatively connected to said tray, a rack and means which, in use, canapply a force to said tubular to move it longitudinally with respect tosaid tray.
 9. An apparatus as claimed in claim 8, wherein said meanscomprises a piston and cylinder.
 10. An apparatus as claimed in claim 8,further comprising a ramp which can be placed against a rig floor,whereby said rack is disposed on said ramp, and said tray can be movedalong said ramp.
 11. An apparatus for delivering a tubular to a wellcenter, comprising: a ramp disposable against a rig floor; a tray forcarrying the tubular up the ramp; and a rack disposed on the ramp toenable the tray to ascend or descend the ramp.
 12. An apparatus fordelivering a tubular to a well center, comprising: a ramp disposableagainst a rig floor; a tray for carrying the tubular up the ramp; andtwo pinions, one mounted adjacent each end of the tray to enable thetray to ascend or descend the ramp.
 13. An apparatus for delivering atubular to a well center, comprising: a ramp disposable against a rigfloor; a tray for carrying the tubular up the ramp; and a pinion mountedon the tray and engageable with a rack to enable the tray to ascend ordescend the ramp.